The present invention relates to data storage systems, and more particularly, this invention relates to data storage systems having independent (e.g., supplemental) servo tracks with velocity encoding and/or longitudinal position encoding embodied therewith.
In magnetic storage systems, data is read from and written onto magnetic recording media utilizing magnetic transducers. Data is written on the magnetic recording media by moving a magnetic recording transducer to a position over the media where the data is to be stored. The magnetic recording transducer then generates a magnetic field, which encodes the data into the magnetic media. Data is read from the media by similarly positioning the magnetic read transducer and then sensing the magnetic field of the magnetic media. Read and write operations may be independently synchronized with the movement of the media to ensure that the data can be read from and written to the desired location on the media.
An important and continuing goal in the data storage industry is that of increasing the density of data stored on a medium. For tape storage systems, that goal has led to increasing the track and linear bit density on recording tape, and decreasing the thickness of the magnetic tape medium. However, the development of small footprint, higher performance tape drive systems has created various problems in the design of a tape head assembly for use in such systems.
In a tape drive system, magnetic tape is moved over the surface of the tape head at high speed. Usually the tape head is designed to minimize the spacing between the head and the tape. The spacing between the magnetic head and the magnetic tape is crucial and so goals in these systems are to have the recording gaps of the transducers, which are the source of the magnetic recording flux in near contact with the tape to effect writing sharp transitions, and to have the read elements in near contact with the tape to provide effective coupling of the magnetic field from the tape to the read elements.
A continuing goal in tape drive systems is effectively managing placement of tracks on tape. In particular, track density is nearly doubling every generation to achieve an approximately 40% per year growth in cartridge capacity within each product family. Another goal is to manage head and electronics designs as channels are added to allow data rate to keep pace with the growing number of data tracks. For example, ongoing goals include using fewer, more integrated ASICs, a least possible number of head channels, and elimination of multiplexing.